sixteen avian influenza (ai) h9n2 viruses were isolated from disease outbreaks in different parts of iranduring (1998–2001). these ai isolates were used for pathogenicity, haemagglutinin (ha) gene variation andphylogenetic analysis. results in both pathogenicity tests and ha gene cleavage site sequence detectionrepresented a non-highly pathogenic feature for all iranian ai isolates studied. the...

pistacia khinjuk (stocks) is a native species that, along with p. atlantica, is widely distributed from eastern to western iran through the makran zone, zagros mountains and the sanandaj-sirjan zone, ranging from 50 to 3300 m above sea level. the identification of resistance gene analogs holds great promise for developing resistant plants. a pcr approach with degenerate primers designed from co...

the ovine melatonin receptor 1a (mtnr1a) and aromatase (cyp19) genes were structurally characterized and the association between their variants and reproductive and growth traits was studied in kurdi sheep at kurdi sheep breeding station located in shirvan, iran. the genomic dna was extracted by guanidine thiocyanate-silica gel method. polymerase chain reaction was carried out to amplify 824 bp...

Some environments are more conducive to pathogen growth than others, and, as a consequence, plants might be expected to invest more in resistance when pathogen growth is favored. Resistance (R-) genes in Arabidopsis thaliana have unusually extensive variation in basal expression when comparing the same R-gene among accessions collected from different environments. R-gene expression variation wa...

The advent of recombinant DNA technology has made possible studies on the organization and expression of eukaryotic genes, which were previously restricted to prokaryotic and viral genes. In large measure, these studies exploit and are dependent upon the availability-through recombinant DNA molecules--of large amounts of individual eukaryotic DNA sequences. They are also dependent upon an accur...